Rapid patterning of nanostructures

ABSTRACT

A process for forming nanostructures comprises generating charged nanoparticles with an electrospray system and introduction of the charged nanoparticles to a substrate, so that the particles adhere to the substrate in order to form the desired structure. The charged nanoparticles may be directed to a target position by at least one deflector in the electrospray apparatus, which may also include a column optic system. The adhered nanoparticles may be sintered to form the structure. The electrospray apparatus may be single source, multi-source injection, or multi-source selection. An array of electrospray apparatuses with deflectors may be used concurrently to form the structure.

RELATED APPLICATIONS

This application is a divisional application of U.S. patent applicationSer. No. 11/330,865, filed Jan. 12, 2006, now U.S. Pat. No. 7,651,926,which claims the benefit of U.S. Provisional Application Ser. No.60/643,254, filed Jan. 12, 2005, the entire disclosure of which isherein incorporated by reference.

U.S. patent application Ser. No. 11/330,865, from which priority isclaimed, is also a continuation-in-part of co-pending U.S. patentapplication Ser. No. 10/444,176, filed May 23, 2003, the entiredisclosure of which is herein incorporated by reference, which claimsthe benefit of U.S. Provisional Application Ser. No. 60/383,396, May 24,2002.

FIELD OF THE INVENTION

This invention relates to nanolithography and, in particular, to thefabrication of two- and three-dimensional functional structures with acharacteristic length scale below 100 nanometers (nm).

BACKGROUND

Nanoelectronic devices with length scales below 100 nm are of greatinterest for the functional semiconductor field. Theoretically, makingdevices with characteristic length scales less than 10 nm is possible,but it takes a long time, is hard to control, and is expensive. Existingmethods for fabricating devices below 100 nm include both top down andbottom up approaches.

Conventional top down approaches using photolithography or electron beamlithography require utilization of photoresists for selective formationof desired materials into functional devices. Because of proximityeffects, photolithography is limited in the resolution achievable.Because of the minimum energy required for photoresist reaction energy,electron beam lithography is limited in the speed obtainable.

Direct-write top down approaches have included atomic force microscopy(AFM), direct writing of liquids, i.e., dip pen nanolithography, andscanning tunneling microscopy (STM) writing of oxides and chargereplicas. These methods suffer from slow speeds, lack of a general setof building materials for fabricating electronic components, and aconstraint to two-dimensional structures.

Existing tools for creating three-dimensional structures employ, forexample, electron beam and ion beam decomposition of chemical vaporprecursors. Such tools have been useful in mask and chip repair and havebeen shown to be capable of writing three-dimensional structures.Typically, organometallic precursor gases adsorbed onto substratesurfaces are decomposed using energy supplied from incident beams,depositing the desired metal or insulator. This technique facilitatesdeposition of nanometer- to micrometer-size structures with nanometerprecision in three dimensions, without supplementary process steps suchas lift-off or etching procedures. Although successful in creating highresolution three-dimensional structures, both scanning electronmicroscopy (SEM) and focused ion beam (FIB) chemical vapor deposition(CVD) suffer from significant contamination by the organic components ofprecursor gases. Carbon contamination from typical precursor gases mayexceed 50%, thus altering device conductivities to levels unacceptablefor many desired applications. Device fabrication by energetic-beam CVDis also constrained by an inherently small number of available precursorgases, thus limiting the variety of materials that can be deposited.Finally, because existing processes are serial and sufficient beamenergy must be applied to decompose the precursor, deposition speeds arevery slow.

In typical currently-employed bottom up approaches, layers areselectively applied to, rather than removed from, a substrate. Forexample, nano-scaled building blocks synthesized precisely by chemistryor other methods may later be assembled by, e.g., self assembly.Presently, the complexity of logic that may be built in this way isextremely limited.

In contrast, nature is excellent at predicated assembly of complexmolecules such as DNA on a scale similar to that of present-daynanostructures. Nature can make precise molecules with enzymes such aspolymerase that typically have extremely low error rates by utilizingfeedback and performing error correction. Direct feedback and errorcorrection are seldom implemented in present fabrication processes, andhence the yield of functional devices is low in comparison to functionalmolecules formed by biological processes.

What has been needed, therefore, is a system for fabrication of two- andthree-dimensional functional structures with a characteristic lengthscale below 100 nm that employs a precise and rapid patterning of highpurity nanoscale building blocks.

SUMMARY

These and other objectives are met by the present invention, which is aprocess for forming nanostructures that comprises generating chargednanoparticles with an electrospray system in a vacuum chamber andintroduction of the charged nanoparticles to a region proximate to acharge pattern, so that the particles adhere to the charge pattern inorder to form the feature. The present invention facilitates a preciseand rapid patterning of high purity nanoscale building blocks in two andthree dimensions in order to build functional ultrahigh density devices.Two- or three-dimensional nanostructures may be formed by rapidlycreating a charge pattern of nanoscale dimensions on a substrate using anormal electron beam or a microcolumn electron beam, generating highpurity nanoscale or molecular size scale building blocks of a first typethat image the charge pattern using the electrospray system, and thenoptionally sintering the building blocks to form the feature.

In one aspect, the present invention is a method for forming a feature,the method including forming a charge pattern on a substrate, the chargepattern having a first type of charge, and introducing nanoscale ormolecular size scale building blocks using an electrospray apparatus ina vacuum chamber to a region proximate the charge pattern, the buildingblocks having a second type of charge and adhering to the charge patternto form the feature. The building blocks may be any suitable material,including nanoparticles and/or organic molecules. The charge pattern maybe formed with an energy beam, such as an ion beam, an electron beam, ormicrocolumn electron beam. The adhered nanoparticles may be globallysintered. The nanoparticles may be directed toward the substrate as astream, such that the nanoparticles adhere only to the charge pattern.The velocity of at least a portion of the plurality of nanoparticles maybe controlled by a metal plate aperture near the tip of the electrosprayapparatus.

The electrospray apparatus may optionally include deflectors to allowdirect deposition of charged particles onto the substrate. It may besingle source or multi-source, allowing spraying of multiple types ofmaterials either simultaneously (injection) or alternately (selection).The electron beam used to create the charge pattern may be singlecolumn, microcolumn, multi-array microcolumn, or any other suitableconfiguration known in the art.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing discussion will be understood more readily from thefollowing detailed description of the invention, when taken inconjunction with the accompanying drawings, in which like referencedfeatures identify common features in corresponding drawings and:

FIG. 1 is a schematic diagram of electrospray equipment for sprayingcharged particles into the vacuum chamber, according to one aspect ofthe present invention;

FIG. 2 is a schematic diagram of microcolumn electron beam equipment forgenerating a low voltage e-beam, according to one aspect of the presentinvention;

FIG. 3 is a schematic diagram of electrospray equipment with deflectorsfor direct deposition of charged particles onto the substrate, accordingto one aspect of the present invention;

FIGS. 4A-D are schematic diagrams of an embodiment of an electronbeam-based nanopatterning process utilizing electrospray equipment withsintering of charged nanoparticles, according to one aspect of thepresent invention;

FIGS. 5A-D are schematic diagrams of an embodiment of an electronbeam-based nanopatterning process utilizing multi-source injectionelectrospray equipment with sintering of charged nanoparticles,according to another aspect of the present invention;

FIGS. 6A-D are schematic diagrams of an embodiment of an electronbeam-based nanopatterning process utilizing multi-source selectionelectrospray equipment with sintering of charged nanoparticles,according to yet another aspect of the present invention;

FIGS. 7A-D are schematic diagrams of an embodiment of a microcolumnelectron beam-based nanopatterning process utilizing electrosprayequipment with sintering of charged nanoparticles according to oneaspect of the present invention;

FIGS. 8A-D are schematic diagrams of an embodiment of a microcolumnelectron beam-based nanopatterning process utilizing multi-sourceinjection electrospray equipment with sintering of charged nanoparticlesaccording to another aspect of the present invention;

FIGS. 9A-D are schematic diagrams of an embodiment of a microcolumnelectron beam-based nanopatterning process utilizing multi-sourceselection electrospray equipment with sintering of charged nanoparticlesaccording to yet another aspect of the present invention;

FIGS. 10A-D are schematic diagrams of an embodiment of a multi-arraymicrocolumn electron beam-based nanopatterning process utilizingelectrospray equipment with sintering of charged nanoparticles accordingto one aspect of the present invention;

FIGS. 11A-D are schematic diagrams of an embodiment of a multi-arraymicrocolumn electron beam-based nanopatterning process utilizingmulti-source injection electrospray equipment with sintering of chargednanoparticles according to another aspect of the present invention;

FIGS. 12A-D are schematic diagrams of an embodiment of a multi-arraymicrocolumn electron beam-based nanopatterning process employingmulti-source selection electrospray equipment with sintering of chargednanoparticles according to yet another aspect of the present invention;

FIGS. 13A-E are schematic diagrams of an embodiment of anelectrospray-based nanopatterning process employing deflectors andsintering of charged nanoparticles according to one aspect of thepresent invention;

FIGS. 14A-C are schematic diagrams of an embodiment of a multi-arrayelectrospray-based nanopatterning process employing a single source anddeflectors with sintering of charged nanoparticles according to oneaspect of the present invention;

FIGS. 15A-C are schematic diagrams of an embodiment of a multi-arrayelectrospray-based nanopatterning process employing a multi-sourceinjection system with deflectors and sintering of charged nanoparticlesaccording to another aspect of the present invention;

FIGS. 16A-C are schematic diagrams of an embodiment of a multi-arrayelectrospray-based nanopatterning process employing a multi-sourceselection system with deflectors and sintering of charged nanoparticlesaccording to yet another aspect of the present invention;

FIG. 17 is a schematic diagram of an embodiment of a differentiallyvacuum pumped electrospray system with lensing according to one aspectof the present invention;

FIG. 18 is a schematic diagram of an embodiment of a system for carryingout electrostatic lithography according to one aspect of the presentinvention;

FIG. 19 is an optical micrograph showing an example of patterned goldfilm fabricated using electrostatic lithography according to one aspectof the present invention; and

FIGS. 20A-W are a set of sequential schematic diagrams depicting anexample step-by-step fabrication of a multi-material multi-layereddevice according to one aspect of the present invention.

DETAILED DESCRIPTION

The present invention is a system for patterning nanoscale buildingblocks for use in fabrication of two- and three-dimensional functionalstructures with a characteristic length scale below 100 nm. In oneembodiment, arbitrary three-dimensional nanostructures are formed byrapidly creating a charge pattern of nanoscale dimensions on a substrateusing a normal electron beam or a microcolumn electron beam, generatinghigh purity molecular size-scale building blocks (MSSBBs) of a firsttype that image the charge pattern, and then optionally sintering orotherwise changing the binding between the MSSBBs and themselves or thesubstrate for the purpose of forming, for example, a locally solid layerdelineated by the charge pattern, or to cause the MSSBBs to becomeattached to the surface or other MSSBBs. In some embodiments, nanoscalebuilding blocks (NSBBs) may be used to image the charge pattern. MSSBBsor NSBBs may be any organic or inorganic molecule, such as DNA,proteins, nucleotides, amino acids, insulating nanoparticles,semiconductor nanoparticles, metal nanoparticles, nanotubes ornanowires. In a preferred embodiment, MSSBBs are nanoparticles, whichmay have dimensions ranging from 1 nm to more than 100 nm. Morespecifically, when the charged nanoparticles are introduced in proximityto the charge pattern, the nanoparticles are attracted to the pattern,thereby “imaging” the charge pattern.

In one embodiment of the present invention, positively chargednanoparticles induced by electrospray are attracted to the negativecharge on a surface of the substrate. Negatively charged nanoparticlesinduced by electrospray are attracted to the positive charge on asurface of the substrate. The process may be repeated with nanoparticlesof a second type to create arbitrary three-dimensional nanostructures.In addition to charged inorganic nanoparticles, organic molecules thathave an affinity for a charge pattern or which themselves can be chargedby the electrospray voltage control system, and thus have an affinityfor a charge pattern, may also be similarly patterned. The chargepattern may be created and represented digitally, or it may be used tocontrol the action of an electron beam or microcolumn electron beam.

An alternative approach to creating arbitrary three-dimensionalnanostructures of high purity involves directly spraying chargednanoparticles using an electrospray apparatus with a short column opticsystem and deflectors, and then sintering the particles via anadditional global heating source to form a locally solid layerdelineated by the charge pattern. The short column optic system focusescharged nanoparticles to the desired point and the deflectors of theelectrospray move the point of spray into the specified place.

Among the many applications of the present invention, it may be used tocreate electronic structures in order to place additional components ona pre-existing semiconductor chip made by conventional methods. Thisprocess is highly versatile in comparison to existing technologiesbecause of the wide variety of materials that may be sprayed in order toform charged nanoparticles, including, but not limited to, metals,inorganic semiconductors, insulators, DNA, proteins, nanotubes, andnanowires. Nanosize materials can be dispersed in any solvent, such as apolar solvent or nonpolar solvent, which has a certain vapor pressure,so that a large class of materials can be sprayed in order to producenanosize particles with positive or negative charges.

In some embodiments, a patterning method using an electrospray systemmay provide a higher resolution and faster throughput than theconventional photolithography method employing photoresists. Theconventional method has a limit of resolution that is 5 nm to severalhundred nm, depending on the thickness of the photoresists. Using anelectron beam to pattern the photoresist may enhance the resolution, butit decreases the process speed. However, patterning particles usingelectrospray does not require use of photoresists. Moreover, a lowdosage of electron beam is enough to put the charge on the substrate,since it does not require any chemical reaction, thereby contributing tothe enhancement of process speed.

In alternative embodiments, other patterning methods are possible whichmay give higher resolution. For example, instead of patterning onlynegative charges with a normal electron beam or a microcolumn electronbeam, negative charges as well as positive charges may be patterned indistinct areas using a dual-beam, scanning electron, and/or focused ionbeam source.

FIG. 1 is a schematic diagram of electrospray equipment for sprayingcharged particles into a vacuum chamber, according to one aspect of thepresent invention. In FIG. 1, charged nanoscale particle 107 isdispersed from electrospray equipment 100. Solution 101 of particles andsolvent is propelled through sharp needle 102 by the effect of a voltagedifferential between tip 103 of needle 102 and plate 104. Solution 101can be made of any particle, such as, for example, insulatingnanoparticles, semiconductor nanoparticles, metal nanoparticles, DNA,proteins, nanotubes, nanowires, and polar or nonpolar solvents. In someembodiments, sharp needle 102 may be made of High Performance LiquidChromatography (HPLC) column, drawn glass tubes, fused silica, or anyother suitable material or construction known in the art. Metal plate109 provides high voltage at tip 103 of inlet needle 102. This voltagecan be positive or negative. Positive voltage at tip 103 induces apositive liquid nanosize particle 107 and negative voltage at tip 103induces a negative liquid nanosize particle. Metal plate 104 has lowervoltage than plate 109, driving movement of particle 107 in specificdirection 108 through the action of the resulting electric field. Metalplates 105 and 106 also have voltages on them, focusing liquidnanoparticles 107 to a single point. Metal plates 104, 105, 106 may haveeither positive or negative voltages, depending on the voltage given toplate 109. Nanoparticles 107 coming through electrospray system 100 willtypically be of a size ranging from 1 nm to more than 100 nm.

The velocity of the nanoparticles may be controlled. The velocity of atleast a portion of the plurality of nanoparticles may be reduced in theregion proximate the charge pattern. The velocity of at least a portionof the plurality of nanoparticles may be controlled by an electric fieldthat may be alternating. The velocity of at least a portion of theplurality of nanoparticles may be controlled by a magnetic field thatmay be alternating. In a preferred embodiment, the velocity of at leasta portion of the plurality of nanoparticles is controlled by a metalplate aperture near the tip of the electrospray apparatus.

FIG. 2 is a schematic diagram of microcolumn electron beam equipment forgenerating a low voltage e-beam, according to one aspect of the presentinvention. In FIG. 2, low energy electron beam 206 is emitted frommicrocolumn electron beam equipment 200. Electron emitter 201 may be alow power Schottky emitter generating electrons by thermionic emission,a field induced emitter generating electrons by high voltage at thetungsten tip or a tip-attaching carbon nanotube, or any other suchdevice known in the art. Emitted electron beam 202 is focused byextractor, anode, and aperture plates 203 by controlling the voltage. Insome embodiments, plates 203 may be made of silicon substrate with pyrexspacer using anodic bonding technique, of other insulating material suchas Teflon, or of ceramic.

Deflectors 204 change the trajectory of the electron beam through theaction of the electric field. For example, an electric field created inthe X direction by a voltage difference in a silicon plate with metalwire induces the path of electron beam 202 to move in the X direction.Similarly, an electric field created in the Y direction by a voltagedifference in a specific silicon plate with metal wire induces the pathof electron beam 202 to move in the Y direction. In some embodiments,deflectors 204 may be comprised of more than four plates (for example,eight plates), in order to provide more precise control of the electronbeam. In other embodiments, deflectors 204 may comprise two pairs in theZ direction that induce a beam path normal to the substrate, even thoughthe desired target of the beam is not at the center of the tip.Electrostatic lenses 205 focus electron beam 202 and select particularelectron beams by means of negatively applied voltage at lens 205.Electrons 206 coming out of microcolumn electron beam system 200 have alow energy, ranging from lower than 10 eV to 1 KeV. This low energy ofthe emitted electrons may enhance the resolution of charged pattern,because a low energy electron cannot disperse widely when being attachedto the surface.

FIG. 3 is a schematic diagram of electrospray equipment with deflectors,used for direct deposition of charged particles onto the substrateaccording to one aspect of the present invention. In FIG. 3, chargednanoscale particle 301 is emitted from electrospray equipment 300 havingdeflectors 307. Solution 301 of particles and solvent is propelledthrough sharp needle 302 by the effect of a voltage differential betweentip 303 of needle 302 and plate 304. Solution 301 can be made of anyparticle such as, for example, insulating nanoparticles, semiconductornanoparticles, metal nanoparticles, DNA, proteins, nanotubes, nanowires,and polar or nonpolar solvents. In some embodiments, sharp needle 302may be made of High Performance Liquid Chromatography (HPLC) column,drawn glass tubes, or fused silica. Metal plate 309 provides a highvoltage at tip 303 of inlet needle 302. This voltage can be positive ornegative. A positive voltage of the tip induces a positive liquidnanosize particle 310, whereas a negative voltage of the tip induces anegative liquid nanosize particle. Metal plate 304 has lower voltagethan plate 309, generating the movement of particle in specificdirection 311 by action of the electric field. Metal plates 305 and 306also have voltages on them, focusing the liquid nanoparticles to asingle point. The voltages on metal plates 304, 305, 306 may be positiveor negative, depending on the voltage provided at plate 309. Deflectors307 operate to change the trajectory of positively or negatively chargednanoparticles by action of the electric field. In some embodiments,deflectors 307 may have more than four plates for more precise controlof the charged nanoparticles. In other embodiments, deflectors 307 maycomprise two pairs in the Z direction that induce a beam path normal tothe , even though the desired target of the beam is not at the center oftip 303. Electrostatic lenses 308 focus deflected nanoparticles withpositive or negative charges through positively or negatively appliedvoltage in lenses 308. Nanoparticles 310 coming through electrosprayapparatus 300 will typically range in size from 1 nm to more than 100nm.

FIGS. 4A-D are schematic diagrams of an embodiment of an electronbeam-based nanopatterning process utilizing electrospray equipment withsintering of charged nanoparticles, according to one aspect of thepresent invention. In FIGS. 4A-D, single electron beam 402 issimultaneously incident in parallel on substrate 404, thereby developingcharge pattern 403. Electron beam 402 may be used for the fabrication offeatures having nanoscale dimensions. In some embodiments, electron beam402 may be an ion beam or a photon beam. Electron beam 402 may have afirst type of charge, i.e., a negative charge, and is generated byelectron beam source 401. Electron beam source 401 may be any suitablesource known in the art, such as, for example, an environmental scanningelectron microscope (ESEM) such as the XL-30 ESEM-FEG manufactured byFEI Company, Hillsboro, Oreg. Electron beam 402 may optionally bedeflected by electrostatic steering plates. Electron beam 402 writescharge pattern 403, also referred to as a charge replica, onto substrate404. In the embodiment of FIG. 4A, the pattern is negatively charged.

Substrate 404 may be formed of any suitable material known in the art,such as, for example, an electret, i.e. a dielectric material capable ofstoring charge, such as mylar, poly(methylmethacrylate), SiO₂, orCaTiO₃. Substrate 404 may be obtained from, for example, GoodfellowCorporation, based in Pennsylvania. In some embodiments, an ion beam[see, e.g., Fudouzi et al., Adv. Mater 14 1649 (2002), using a 30 keVGa⁺ ion beam to write positively charged patterns in CaTiO₃], an atomicforce microscope (AFM) writing head [see, e.g., P. Mesquida and A.Stemmer, Adv. Mater. 13 1397 (2001), inducing negative or positivecharge patterns in poly(tetra-fluoroethylene) (PTFE) by applying voltagepulses of ±15-20V to the tip], microcontact stamping of charge [see,e.g., H. O. Jacobs and G. M. Whitesides, Science 291 1763 (2001),submicron trapping of charge in thin layers of PMMA on n-doped siliconby applying 10-20 V between the conductive silicon support and apatterned gold-coated poly (dimethylsiloxane) stamp], or any suitabledevice known in the art may be used to generate charge pattern 203.

In FIG. 4A, inside a vacuum chamber ranging from 1.0*10-4 mbarr to morethan 1.0*10-7 mbarr, electrospray system 100 generates positively ornegatively charged liquid nanosize particles 107 in direction 108 ofcharge pattern 403. In FIG. 4B, a plurality of positively chargednanosize particles 107 deposit onto a surface of substrate 404 andarrange themselves on charge pattern 403. In FIG. 4C, global heatingsource 405 heats substrate 404, thereby sintering nanoparticles 107 toform continuous structure 409 (FIG. 4D) that includes nanoparticles 107without any solvents. Global heating source 405 may be any suitabledevice known in the art, such as, for example, a hot plate or a laser.An advantage of this process of the present invention is that it may bescaled up to many thousands of beams or more, and therefore thefabrication speed may be increased by many orders of magnitude.

FIGS. 5A-D are schematic diagrams of an embodiment of an electronbeam-based nanopatterning process employing multi-source injectionelectrospray equipment and sintering of charged nanoparticles accordingto another aspect of the present invention. In FIGS. 5A-D, singleelectron beam 402 is simultaneously incident in parallel on substrate404, thereby developing charge pattern 403. Electron beam 402 may beused for the fabrication of features having nanoscale dimensions. Asmentioned above for FIGS. 4A-D, charge pattern 403 may be established byany of the several methods known in the art, such as, for example,electron beam or ion beam. Electron beam 402 may be optionally deflectedby electrostatic steering plates. Electron beam 402 writes chargepattern 403 onto substrate 404. In the embodiment shown in FIG. 5A, thepattern is negatively charged.

Substrate 404 may be formed of, for example, an electret. In FIG. 5A,inside a vacuum chamber ranging from 1.0*10-4 mbarr to more than1.0*10-7 mbarr, multi-source electrospray system 510 generatespositively or negatively charged liquid nanosize particles 107 indirection 108 of charge pattern 403. Multi-source inlet electrospraysystem 510 may spray several different materials, depending on the sprayneedle design. For purity reasons, one or more of the inlet tubes maycontain solvent that cleans the path of solution. In FIG. 5B, aplurality of positively charged nanosize particles 107 deposit onto thesurface of substrate 404 and arrange themselves on charge pattern 403.Because of the multiple inlet electrospray system, several materials,such as insulator, semiconductor, or metal materials, can image apattern on the same plate without the need to take substrate 404 out ofthe vacuum chamber. In FIG. 5C, global heating source 405 heatssubstrate 404, thereby sintering nanoparticles 107 to form continuousstructure 409 (FIG. 5D) that includes nanoparticles 107 without anysolvents. Global heating source 405 may be any suitable device known inthe art, such as, for example, a hot plate or a laser.

FIGS. 6A-D are schematic diagrams of an embodiment of an electronbeam-based nanopatterning process employing multi-source selectionelectrospray equipment and sintering of charged nanoparticles, accordingto yet another aspect of the present invention. In FIGS. 6A-D, singleelectron beam 402 is simultaneously incident in parallel on substrate404, thereby developing charge pattern 403. Electron beam 402 may beused for the fabrication of features having nanoscale dimensions. Chargepattern 403 may be produced by any of several methods known in the art,such as, but not limited to, electron beam or ion beam. Electron beam402 may optionally be deflected by electrostatic steering plates.Electron beam 402 writes charge pattern 403 onto substrate 404. In theembodiment shown in FIG. 6A, the pattern is negatively charged.Substrate 404 may be formed of, for example, an electret.

In FIG. 6A, inside a vacuum chamber ranging from 1.0*10-4 mbarr to morethan 1.0*10-7 mbarr, multi-source selection electrospray system 620generates positively or negatively charged liquid nanosize particles 107in direction 108 of charge pattern 403. Multi-source selectionelectrospray system 620 may spray several materials, depending on thespray needle design. For purity reasons, one or more of the inlet tubesmay contain solvent that cleans the path of solution. In FIG. 6B, aplurality of positively charged nanosize particles 107 deposit onto thesurface of substrate 404 and arrange themselves on charge pattern 403.Because of the multi-source selection electrospray system, severalmaterials, such as, for example, insulator, semiconductor, or metalmaterials, can image a pattern on the same plate without takingsubstrate 404 out of the vacuum chamber. In FIG. 6C, global heatingsource 405 heats substrate 404, thereby sintering nanoparticles 107 toform continuous structure 409 (FIG. 6D) that includes nanoparticles 107without any solvents.

FIGS. 7A-D are schematic diagrams of an embodiment of a microcolumnelectron beam-based nanopatterning process utilizing electrosprayequipment and sintering of charged nanoparticles, according to oneaspect of the present invention. In FIGS. 7A-D, single microcolumnelectron beam system 200 generates electron beam 206 simultaneouslyincident in parallel on substrate 404, thereby developing charge pattern403. Electron beam 206 may be used for the fabrication of featureshaving nanoscale dimensions. Electron beam 206 may optionally bedeflected by electrostatic steering plates. Electron beam 206 writescharge pattern 403 onto substrate 404. In the embodiment shown in FIG.7A, the pattern is negatively charged. Substrate 404 may be formed of,for example, an electret. Inside a vacuum chamber ranging from 1.0*10-4mbarr to more than 1.0*10-7 mbarr, electrospray system 100 generatespositively or negatively charged liquid nanosize particles 107 indirection 108 of charge pattern 403. As seen in FIG. 7B, a plurality ofpositively charged nanosize particles 107 deposit onto the surface ofsubstrate 404 and arrange themselves on charge pattern 403. In FIG. 7C,global heating source 405 heats substrate 404, thereby sintering thenanoparticles 107 to form continuous structure 409 (FIG. 7D) thatincludes nanoparticles 107 without any solvents.

FIGS. 8A-D are schematic diagrams of an embodiment of a microcolumnelectron beam-based nanopatterning process employing multi-sourceinjection electrospray equipment and sintering of charged nanoparticles,according to another aspect of the present invention. In FIGS. 8A-D,single microcolumn electron beam system 200 generates electron beam 206simultaneously incident in parallel on substrate 404, thereby developingcharge pattern 403. Electron beam 206 may be used for the fabrication offeatures having nanoscale dimensions. Electron beam 206 may optionallybe deflected by electrostatic steering plates. Electron beam 206 writescharge pattern 403 onto substrate 404. In the embodiment shown in FIG.8A, the pattern is negatively charged. Substrate 404 may be formed of,for example, an electret.

In FIG. 8A, inside a vacuum chamber ranging from 1.0*10-4 mbarr to morethan 1.0*10-7 mbarr, multi-source electrospray system 510 generatespositively or negatively charged liquid nanosize particles 107 indirection 108 of charge pattern 403. Multisource inlet electrospraysystem 510 may spray several materials, depending on the spray needledesign. For purity reasons, one of the inlet tubes may contain solventthat cleans the path of solution. In FIG. 8B, a plurality of positivelycharged nanosize particles 107 deposit onto the surface of substrate 404and arrange themselves on charge pattern 403. Because of the multipleinlet electrospray system 510, several materials, such as insulator,semiconductor, or metal materials, can image pattern 403 on the sameplate without taking substrate 404 out of the vacuum chamber. In FIG.8C, global heating source 405 heats substrate 404, thereby sinteringnanoparticles 107 to form continuous structure 409 (FIG. 8D) thatincludes nanoparticles 107 without any solvents.

FIGS. 9A-D are schematic diagrams of an embodiment of a microcolumnelectron beam-based nanopatterning process employs multi-sourceselection electrospray equipment and sintering of charged nanoparticles,according to yet another aspect of the present invention. In FIGS. 9A-D,single microcolumn electron beam system 200 generates electron beam 206simultaneously incident in parallel on substrate 404, thereby developingcharge pattern 403. Electron beam 206 may be used for the fabrication offeatures having nanoscale dimensions and may optionally be deflected byelectrostatic steering plates. Electron beam 206 writes charge pattern403 onto substrate 404. In the embodiment shown in FIG. 9A, the patternis negatively charged. Substrate 404 may be formed of, for example, anelectret.

In FIG. 9A, inside a vacuum chamber ranging from 1.0*10-4 mbarr to morethan 1.0*10-7 mbarr, multi-source selection electrospray system 620generates positively or negatively charged liquid nanosize particles 107in direction 108 of charge pattern 403. Multi-source selectionelectrospray system 620 may spray several materials, depending on thespray needle design. For purity reasons, one or more of the inlet tubesmay contain solvent that cleans the path of solution. In FIG. 9B, aplurality of positively charged nanosize particles 107 deposit onto thesurface of substrate 404 and arrange themselves on charge pattern 403.Because of the multi-source selection electrospray system 620, severalmaterials, such as insulator, semiconductor, or metal materials, canimage pattern 403 on the same plate without taking substrate 404 out ofthe vacuum chamber. In FIG. 9C, global heating source 405 heatssubstrate 404, thereby sintering nanoparticles 107 to form continuousstructure 409 (FIG. 9D) that includes nanoparticles 107 without anysolvents.

FIGS. 10A-D are schematic diagrams of an embodiment of a multi-arraymicrocolumn electron beam-based nanopatterning process employingelectrospray equipment and sintering of charged nanoparticles accordingto one aspect of the present invention. In FIGS. 10A-D,multi-microcolumn electron beam system 1010 generates array of electronbeams 1001 simultaneously incident in parallel on substrate 1003,thereby developing charge pattern 1002. Charge pattern 1002 is thuscreated in a single step, rather than by the scanning of a single beamacross entire substrate 1003 multiple times. Array of electron beams1001 may be used for the fabrication of features having nanoscaledimensions. Array of electron beams 1001 may be optionally deflected byelectrostatic steering plates. Array of electron beams 1001 writescharge pattern 1002 onto substrate 1003. In the embodiment shown in FIG.10A, the pattern is negatively charged. Substrate 1003 may be formed ofany suitable material known in the art, such as, for example, anelectret, i.e., a dielectric material capable of storing charge.

In FIG. 10A, inside a vacuum chamber ranging from 1.0*10-4 mbarr to morethan 1.0*10-7 mbarr, electrospray system 100 generates positively ornegatively charged liquid nanosize particles 107 in direction 108 ofcharge pattern 1002. In FIG. 10B, a plurality of positively chargednanosize particles 0107 deposit onto the surface of substrate 1003 andarrange themselves on charge pattern 1002. In FIG. 10C, global heatingsource 1004 heats substrate 1003, thereby sintering nanoparticles 107 toform continuous structure 409 (FIG. 10D) that includes nanoparticles 107without any solvents. Global heating source 1004 may be any suitabledevice known in the art, such as, for example, a hot plate or a laser.

FIGS. 11A-D are schematic diagrams of an embodiment of a multi-arraymicrocolumn electron beam-based nanopatterning process employingmulti-source injection electrospray equipment and sintering of chargednanoparticles, according to another aspect of the present invention. InFIGS. 11A-D, multi-microcolumn electron beam system 1010 generates arrayof electron beams 1101 simultaneously incident in parallel on substrate1103, thereby developing charge pattern 1102. Charge pattern 1102 isthus created in a single step rather than by the scanning of a singlebeam across entire substrate 1103 multiple times. Array of electronbeams 1101 may be used for the fabrication of features having nanoscaledimensions. Array of electron beams 1101 may optionally be deflected byelectrostatic steering plates. Array of electron beams 1101 writescharge pattern 1102 onto substrate 1103. In the embodiment shown in FIG.11A, the pattern is negatively charged. Substrate 1103 may be formed of,for example, an electret.

In FIG. 11A, inside a vacuum chamber ranging from 1.0*10-4 mbarr to morethan 1.0*10-7 mbarr, multi-source electrospray system 510 generatespositively or negatively charged liquid nanosize particles 107 indirection 108 of charge pattern 1102. Multi-source inlet electrospraysystem 510 may spray several materials, depending on the spray needledesign. For purity reasons, one or more of the inlet tubes may containsolvent that cleans the path of solution. In FIG. 11B, a plurality ofpositively charged nanosize particles 107 deposit onto the surface ofsubstrate 1103 and arrange themselves on charge pattern 1102. Because ofthe multiple inlet electrospray system, several materials, such asinsulator, semiconductor, or metal materials, can image pattern 1102 onthe same plate without taking substrate 1103 out of the vacuum chamber.In FIG. 11C, global heating source 1104 heats substrate 1103, therebysintering nanoparticles 107 to form continuous structure 409 (FIG. 11D)that includes nanoparticles 107 without any solvents. Global heatingsource 1104 may be any suitable device known in the art, such as, forexample, a hot plate or a laser.

FIGS. 12A-D are schematic diagrams of an embodiment of a multi-arraymicrocolumn electron beam-based nanopatterning process employingmulti-source selection electrospray equipment and sintering of chargednanoparticles according to yet another aspect of the present invention.In FIGS. 12A-D, multi-microcolumn electron beam system 1010 generatesarray of electron beams 1201 simultaneously incident in parallel onsubstrate 1203, thereby developing charge pattern 1202. Charge pattern1202 is thus created in a single step rather than by the scanning of asingle beam across entire substrate 1203 multiple times. Array ofelectron beams 1201 may be used for the fabrication of features havingnanoscale dimensions and writes charge pattern 1202 onto substrate 1203.Array of electron beams 1201 may optionally be deflected byelectrostatic steering plates. In the embodiment shown in FIG. 12A, thepattern is negatively charged. Substrate 1203 may be formed of anysuitable material known in the art, such as, for example, an electret.

In FIG. 12A, inside a vacuum chamber ranging from 1.0*10⁻⁴ mbarr to morethan 1.0*10⁻⁷ mbarr, multi-source selection electrospray system 620generates positively or negatively charged liquid nanosize particles 107in direction 108 of charge pattern 1202. Multi-source selectionelectrospray system 620 may spray several materials, depending on thespray needle design. For purity reasons, one of the inlet tubes maycontain solvent that cleans the path of solution. In FIG. 12B, aplurality of positively charged nanosize particles 107 deposit onto thesurface of substrate 404 and arrange themselves on charge pattern 1202.Because of the multi-source selection electrospray system, severalmaterials, such as, for example, insulator, semiconductor, or metalmaterials, can image pattern 1202 on the same plate without takingsubstrate 1203 out of the vacuum chamber. As seen in FIG. 12C, globalheating source 1204 heats substrate 1203, thereby sintering thenanoparticles 107 to form continuous structure 409 (FIG. 12D) thatincludes nanoparticles 107 without any solvents. Global heating source1204 may be any suitable device known in the art, such as, for example,a hot plate or a laser.

FIGS. 13A-E are schematic diagrams of an embodiment of anelectrospray-based nanopatterning process employing deflectors andsintering of charged nanoparticles, according to one aspect of thepresent invention. In FIGS. 13A-C, charged nanoscale particles 1302 aredispersed from electrospray equipment with deflectors 1300, 1310, 1320,respectively. A solution of particles and solvent is propelled throughthe sharp needle by the effect of a voltage differential between the tipof the needle and the plate. The solution can be made of any particle,including, but not limited to, insulating nanoparticles, semiconductornanoparticles, metal nanoparticles, DNA, proteins, nanotubes, nanowires,and polar or nonpolar solvents. Charged particles 1302 can be preciselydeposited to specific area 1301 utilizing the deflectors in electrospraysystems 1300, 1310, and 1320. In FIG. 13D, particle 1302 is positivelycharged. Substrate 1303 may be formed of, for example, an electret.Inside a vacuum chamber ranging from 1.0*10⁻⁴ mbarr to more than1.0*10⁻⁷ mbarr, global heating source 1304 heats substrate 1303, therebysintering nanoparticles 1302 to form continuous structure 1305 (FIG.13E) that includes nanoparticles 1302 without any solvents. Globalheating source 1304 may be any suitable device known in the art, suchas, for example, a hot plate or a laser.

FIGS. 14A-C are schematic diagrams of an embodiment of a multi-arrayelectrospray-based nanopatterning process according to one aspect of thepresent invention, having a single source and deflectors and sinteringof charged nanoparticles. In FIGS. 14A-C, charged nanoscale particles1402 are dispensed from multi-array electrospray equipment withdeflectors 1400. Solution 1402 of particles and solvent is propelledthrough the sharp needle by the effect of the voltage differentialbetween the tip of the needle and the plate. In some embodiments,solutions can be made of any particle, such as, but not limited to,insulating nanoparticles, semiconductor nanoparticles, metalnanoparticles, DNA, proteins, nanotubes, nanowires, and polar ornonpolar solvents. In this embodiment, charged particle pattern 1402 iscreated in a single step rather than by the scanning of a singleelectrospray system with deflector across entire substrate 1403 multipletimes.

An array of electrosprays with deflectors 1400 may be used for thefabrication of features having nanoscale dimensions. Charged particles1402 can be deposited to specific area 1401 using the deflectors inmulti-array electrospray system 1400. In the embodiment shown in FIG.14B, the particle is positively charged. Substrate 1403 may be formed ofany suitable material known in the art, such as, for example, anelectret. Inside a vacuum chamber ranging from 1.0*10⁻⁴ mbarr to morethan 1.0*10⁻⁷ mbarr, global heating source 1404 (FIG. 14C) heatssubstrate 1403, thereby sintering nanoparticles 1402 to form continuousstructure 1405 that includes nanoparticles 1402 without any solvents.Global heating source 1404 may be any suitable device known in the art,such as, for example, a hot plate or a laser.

FIGS. 15A-C are schematic diagrams of an embodiment of a multi-arrayelectrospray-based nanopatterning process according to another aspect ofthe present invention, utilizing a multi-source injection system withdeflectors and sintering of charged nanoparticles. In FIGS. 15A-C,charged nanoscale particles 1502 are dispersed from the multi-array andmulti-source inlet electrospray equipment with deflectors 1500.Multi-array and multi-source inlet electrospray system 1500 may sprayseveral materials, depending on the spray needle design. Because of themulti source selection system, several materials, such as insulator,semiconductor, or metal materials, can image a pattern on the same platewithout taking substrate 1504 out of the vacuum chamber. Solution 1502of particles and solvent is propelled through the sharp needle by theeffect of the voltage differential between the tip of the needle and theplate. The solutions can be made of any particle, such as, but notlimited to, insulating nanoparticles, semiconductor nanoparticles, metalnanoparticles, DNA, proteins, nanotubes, nanowires, and polar ornonpolar solvents. In this embodiment, charge particle pattern 1502 maybe created in a single step rather than by the scanning of a singleelectrospray system with deflector across the entire substrate 1503multiple times.

An array of electrosprays with deflectors 1500 may be used for thefabrication of features having nanoscale dimensions. Charged particles1502 can be deposited to specific area 1501 using the deflector inmulti-array electrospray system 1500. In the embodiment shown in FIG.15B, the particle is positively charged. Substrate 1503 may be formed ofany suitable material known in the art, such as, for example, anelectret. Inside a vacuum chamber ranging from 1.0*10⁻⁴ mbarr to morethan 1.0*10⁻⁷ mbarr, global heating source 1504 (FIG. 15C) heatssubstrate 1503, thereby sintering nanoparticles 1502 to form continuousstructure 1505 that includes nanoparticles 1502 without any solvents.Global heating source 1504 may be any suitable device known in the art,such as, for example, a hot plate or a laser.

FIGS. 16A-C are schematic diagrams of an embodiment of a multi-arrayelectrospray-based nanopatterning process according to yet anotheraspect of the present invention, employing a multi-source selectionsystem with deflectors and sintering of charged nanoparticles. In FIGS.16A-C, charged nanoscale particles 1602 are dispersed from themulti-array and multi-source selection electrospray equipment withdeflectors 1600. Multi-array and multi-source inlet electrospray system1600 may spray several materials, depending on the spray needle design.Because of the multi-source selection system, several materials, such asinsulator, semiconductor, or metal materials, can image a pattern on thesame plate without taking substrate 1604 out of the vacuum chamber.Solution 1602 of particles and solvent is propelled through the sharpneedle by the effect of a voltage differential between the tip of theneedle and the plate. Solutions can be made of any particle, such as,but not limited to, insulating nanoparticles, semiconductornanoparticles, metal nanoparticles, DNA, proteins, nanotubes, nanowires,and polar or nonpolar solvents. In this embodiment, charge particlepattern 1602 may be created in a single step, rather than by thescanning of a single electrospray system with deflector across theentire substrate 1603 multiple times. An array of electrosprays withdeflectors 1600 may be used for the fabrication of features havingnanoscale dimensions. Charged particles 1602 can be deposited tospecific area 1601 using the deflectora in multi-array electrospraysystem 1600. In the embodiment shown in FIG. 16B, the particle ispositively charged. Substrate 1603 may be formed of any suitablematerial known in the art, such as, for example, an electret. Inside avacuum chamber ranging from 1.0*10⁻⁴ mbarr to more than 1.0*10⁻⁷ mbarr,global heating source 1604 (FIG. 16C) heats substrate 1603, therebysintering nanoparticles 1602 to form continuous structure 1605 thatincludes nanoparticles 1602 without any solvents. Global heating source1604 may be any suitable device known in the art, such as, for example,a hot plate or a laser.

FIG. 17 is a schematic diagram of an embodiment of a differentiallyvacuum pumped electrospray system with lensing, according to one aspectof the present invention. In FIG. 17, the mechanism of electrosprayallows the spraying of material that is initially in the liquid phase.When spraying such a material into a vacuum, dissolved gas in the liquidor a propensity of the liquid itself to boil may cause large droplets toemerge from the electrospray unit when a spray with nanoscale dropletsis desired. In order to fabricate a more general system, it is sometimesuseful to initially electrospray into a higher pressure region and thentransfer the resultant spray into a lower pressure region. FIG. 17depicts the schematic of a differential vacuum electrospray assembly. Inone embodiment, electrospray needle 1701 and extractor 1702 electrosprayinto first chamber 1710 having pressure p1, which may be at or close toatmospheric pressure. Chamber 1710 is equipped with multistackelectrostatic lens 1703, which can be D.C. only or D.C.+RF and whichcauses the spray to follow trajectory 1705. Chamber 1710 is separatedfrom second chamber 1720 by aperture 1712, which is held at a pressurep2, which is less than pl and which may typically be 10^−3 torr. Chamber1720 may be connected to pump system 1706 for maintaining pressure p2.The purpose of multistack electrostatic lens 1703 is to refocus theelectrosprayed beam so that more of the beam will transfer throughaperture 1712. Likewise, chamber 1720 is separated from chamber 1730,which is held at pressure p3, which is lower than p2 and may typicallybe 10^−6 torr, by aperture 1722. Chamber 1720 is equipped withmultistack electrostatic lens assembly 1704 for the purpose ofrefocusing the electrosprayed beam through aperture 1722.

FIG. 18 is a schematic diagram of an embodiment of a system for carryingout electrostatic lithography according to one aspect of the presentinvention, a system for carrying out structure fabrication by means ofan electrostatic resist. An electrostatic resist utilizes electrons tostore electronic charge in substrates. Each electron stored in thesubstrate generates an electric field around it. The electric field canpolarize and attract a cluster with hundreds of atoms towards theelectron storage spot. Thus, each electron has the capability ofattracting hundreds of atoms to it. This resist is thus very highlyamplified due to electrostatics. The efficiency of the process allowsthe usage of exposure doses as low as 0.01 μc/cm², which is at least 100times lower than most commercially available resists. The differencebetween an electrostatic resist and the electrosprayed functionalmaterials discussed above is that the resist serves as a surface uponwhich a functional material may be deposited and which may later belifted off

FIG. 18 depicts a schematic of a single-pump down system forelectrostatic lithography. In FIG. 18, vacuum chamber 2001 encloseselectron beam column 2002, electrospray nozzle with electrostatic lensassembly 2003, thin film deposition source 2005, and reactive ion etchcolumn 2006. Electron beam column 2002 generates accelerated electrons,which deposit charge 2007 onto insulating substrate 2008. Theelectrospray source generates positively charged nanoparticles ornanodroplets 2004, which are then attracted to the oppositely chargedsubstrate. Nanoparticles could be any suitable type of particles knownin the art, such as, but not limited to, metals (e.g. Au, Al),insulators (e.g. SiO2) or semiconductors (Si). Nanodroplets may befluids or gases that adhere to the charged regions and may includeconventional resist materials such as, but not limited to, PMMA, whichmay require further optical or thermal treatment to serve as effectiveresists, or volatile solvent (e.g. Acetone), which may require that thecharged surface be cooled to the freezing point of the solvent.Alternatively, instead of an electrospray source, there may be anothercharged particle or charged ion source, including ion sources (e.g. Xe)to deposit ions onto the charged surface that has been cooled to thepoint in which the sticking probability of the ion is high.

After nanoparticles or nanodroplets decorate the electronic chargepattern, and allowing for the fact that in certain cases suchnanoparticles or nanodroplets may be further heat, chemically, oroptically treated to form a more perfect barrier, a thin film of anymaterial of choice is deposited on the substrate by the thin filmdeposition source. The thin film deposition source could be any suitabledevice known in the art, such as, but not limited to, a sputterer, athermal or electron beam evaporator, or a chemical vapor deposition(CVD) source. The thin film deposition source can be used to depositmetal (e.g Au, Ag, Al, W, Ti, organic conductor), insulator (e.g. SiO2,TiO2, organic insulator), or semiconductor (Si, GaAs, InP, Ge, organicsemiconductor such as pentacene) materials, or any suitable materialknown in the art. Any material of choice can be deposited in thin-filmform. Reactive ion etch column 2006 then etches away the nanoparticle ornanodroplet resist film, along with material deposited on them. Apatterned thin film of material remains on the substrate.

FIG. 19 is an optical micrograph showing an example of a patterned goldfilm fabricated using electrostatic lithography according to one aspectof the present invention. In this example, charge from an electron beamwas patterned in an L shape onto a polyimide substrate. The substratewas then dusted with particles that were attracted to the charged regionand Au was subsequently evaporated onto the entire substrate. Finallythe particles were lifted off, leaving the resulting pattern.

The present system may be used to create a variety of devices andstructures, including 1-, 2-, and 3-dimensional nanostructures,micro-electro-mechanical systems, and logic. Some of these structuresrequire the deposition of several materials, and the present inventionprovides mechanisms for doing so. FIGS. 20A-W depict a process flow forcreation of a complimentary metal oxide semiconductor (CMOS), a processthat involves the patterned placement of a number of different materialsin three dimensions and which could be used to create a large fractionof existing logic devices. The process description of FIGS. 20A-Wprovides a particular sequence of process steps, but it should beunderstood that there are a large number of other specific processeswhich are possible through differently combining the mechanisms forpatterning and deposition previously described herein.

FIGS. 20A-W are a set of sequential schematic diagrams depicting anexample step-by-step fabrication of a multi-material multi-layereddevice according to one aspect of the present invention. As shown inFIG. 20A, step 1 of the process begins with substrate 1800 (e.g. p typeSi) and heating and cooling plate 1810. As shown in FIG. 20B, in step 2,oxide (SiO2) 1801 is grown through any suitable method known in the art,such as, for instance, chemical vapor deposition (CVD) onto substrate1800. As shown in FIG. 20C, in step 3, oxide 1801 is spatiallypatterned, such as by standard lithographic patterning or byelectrostatic patterning. As shown in FIG. 20D, in step 4, the entiresurface is covered with volatizable charge retention layer 1802 (VCRL,e.g. Xenon or a high vapor pressure liquid), which may be adhered to thesurface from the gas or liquid phase by employing cooling plate 1810 tohold the surface at a temperature such that the sticking potential ofthe volatizable charge retention layer 1802 freezes (liquid) or has ahigh striking potential (gas). Charge retention layer 1802 maypreferably be a single monolayer. Charge 1803 is then deposited atselected spots 1804 of charge retention layer 1802, such as may beaccomplished with an electron beam gun or any other suitable methodknown in the art.

As shown in FIG. 20E, in step 5, positively charged electrosprayparticles 1805 (e.g. liquid dopant, such as, for example, thosemanufactured by Honeywell Electronics Materials Corp. or predoped liquidsilanes) are made incident to the charged surface such that thepositively charged particles are attracted 1806 to the surface in theregion where negative charge has been patterned. As shown in FIG. 20F,in step 6, n-doped well 1807 is formed be thermal diffusion of thepatterned dopant particles. This step also volatilizes VCRL 1802. Asshown in FIG. 20G, in step 7, VCRL 1802 is globally deposited and ebeam1820 is used to deposit charge patterns 1821 and 1822 for patterning ofthe gate oxide in the CMOS device. As shown in FIG. 20H, in step 8,electrosprayed oxide 1823 (e.g. nanoparticle silica or spin on glass(SOG)) forms patterns 1824 and 1825.

As shown in FIG. 20I, in step 9, such patterns are then converted tofunctional gate oxide regions 1826 and 1827, such as may be accomplishedby thermally heating the surface by means of heating and cooling plate1810. As shown in FIG. 20J, in step 10, electron beam 1831 depositscharge patterns 1832 and 1833 to serve as a charge template for theformation of a patterned semiconductor region. As shown in FIG. 20K, instep 11, a semiconductor, which may be, for example, but not limited to,a charged liquid silane or Si nanoparticle emergent from an electrosprayunit, is made incident on the charge template regions to form asemiconducting region. Such regions may then be converted, such as bythermal means, to functional patterned semiconductor regions 1834. Suchprocessing may include means to convert inorganic semiconductingmaterials to nearly single crystalline materials such as laserannealing. Alternatively, some semiconducting materials, such as organicsemiconductors, may not require any additional processing to be active.As shown in FIG. 20L, in step 12, VCRL 1802 is globally deposited andebeam 1841 is used to deposit charge patterns 1842 for n-type source anddrain formation.

As shown in FIG. 20M, in step 13, electrosprayed n-type semiconductor(e.g. nanoparticle n-doped Si or n-doped silane) or n-type or liquid(e.g. Honeywell Corp.) is deposited onto the charge pattern to formn-type dopant region 1843 which may then be activated to form n-dopedsource and drain regions 1844 (FIG. 20N—step 14). As shown in FIG. 20-O,in step 15, a VCRL is globally deposited and ebeam 1851 is used todeposit charge patterns 1852 for n-type source and drain formation. Asshown in FIG. 20P, in step 16, electrosprayed p-type semiconductor (e.g.nanoparticle p-doped Si or p-doped silane) or p-type or liquid (e.g.Honeywell Corp.) is deposited onto the charge pattern to form p-typedopant region 1853, which may then be activated to form p-doped sourceand drain regions 1854 (FIG. 20Q—step 17).

As shown in FIG. 20R (Step 18), global oxide (e.g. SiO2) 1861 isdeposited and, in FIG. 20S (step 19), patterned to form patterned oxideregions 1862 and 1863. Such patterning may be carried out in situ by themeans of an electrostatic resist. Alternatively, steps 18 and 19 may becombined by means of the methods described herein of patterning a chargeretention layer, forming a patterned latent charge image, developingthat image with a suitable functional material precursor (e.g. spin onglass (SOG), and then converting, such as by thermal means, the oxideprecursor to a functional oxide.

As shown in FIG. 20T, in step 20, VCRL 1871 is globally deposited and,in FIG. 20U (step 21), ebeam 1872 is used to deposit charge patterns1873 for patterning of the metal contact in the CMOS device. As shown inFIG. 20V, in step 22, the charge pattern may be developed with anelectrosprayed metal (e.g. nanoparticle metal or liquid metallo-organicprecursor) and converted, such as by thermal means, to form functionalmetal contact regions 1874. Repetition of the oxide and metal depositionsteps results in structures such as those shown in FIG. 20W, comprisingmultiple metal 1881, 1883 and oxide 1882 layers and regions.

It is to be understood that the examples presented are illustrative of abroad range of other examples that may be constructed by combining stepsinvolving the mechanisms of patterning and deposition detailed above.Such a combination of steps may be employed to create a wide variety ofpatterns of single or multiple materials in three dimensions. Each ofthe various embodiments described above may be combined with otherdescribed embodiments in order to provide multiple features.Furthermore, while the foregoing describes a number of separateembodiments of the apparatus and method of the present invention, whathas been described herein is merely illustrative of the application ofthe principles of the present invention. Other arrangements, methods,modifications and substitutions by one of ordinary skill in the art aretherefore also considered to be within the scope of the presentinvention, which is not to be limited except by the claims that follow.

1. A method for forming a structure, comprising the steps of: formingcharged nanoparticles using an electrospray apparatus; and directing thecharged nanoparticles directly to a desired location on a substratewithout a charge pattern.
 2. The method of claim 1, wherein the chargednanoparticles are directed to a target position by at least onedeflector in the electrospray apparatus.
 3. The method of claim 2,wherein the electrospray apparatus further includes a short column opticsystem.
 4. The method of claim 2, further comprising the step ofconcurrently using an array of additional electrospray apparatuses withdeflectors to form the structure.
 5. The method of claim 1, furthercomprising the step of globally sintering the adhered nanoparticles. 6.The method of claim 1, wherein the electrospray apparatus is a singlesource electrospray apparatus.
 7. The method of claim 1, wherein theelectrospray apparatus is a multi-source injection electrosprayapparatus.
 8. The method of claim 1, wherein the electrospray apparatusis a multi-source selection electrospray apparatus.
 9. The method ofclaim 1, further comprising the step of controlling a velocity of thenanoparticles.
 10. The method of claim 8, wherein the velocity of atleast a portion of the plurality of nanoparticles is controlled by avoltage differential between the tip of the electrospray apparatus andat least one aperture plate.
 11. The method of claim 1, wherein thenanoparticles are selected from the group consisting of: insulatingnanoparticles, semiconductor nanoparticles, metal nanoparticles, DNA,proteins, nanotubes, and nanowires.